1. Field of the Invention
The present invention relates to a wireless communication system, and more particularly to a method and apparatus for channel access in a wireless LAN (WLAN) system.
2. Discussion of the Related Art
Machine Type Communication (MTC) refers to a communication scheme including one or more machines, and may also be referred to as Machine Type Communication (MTC) or Machine To Machine (M2M) communication. In this case, the machine may be an entity that does not require direct handling and intervention of a user. For example, not only a meter or vending machine including a mobile communication module, but also a user equipment (UE) (such as a smartphone) capable of performing communication by automatically accessing the network without user intervention/handling may be an example of such machines. Various examples of such machines may be referred to as MTC devices or MTC UEs. In other words, MTC communication refers to a communication scheme including one or more machines (i.e., one or more MTC devices) without user intervention/handling.
MTC may include Device-to-Device (D2D) communication and communication between an MTC device and an MTC application server, etc. Exemplary communication between the MTC device and the MTC application server includes communication between a vending machine and an application server, communication between a Point of Sale (POS) device and an application server, and communication between an electric meter, a gas meter or a water meter and a server. MTC-based communication applications may include security, transportation, healthcare, etc.